Process and apparatus for making concentrated carbon dioxide



. 1,61 March l, 1927. v v DREWSEN w 9336 PROCESS AND APPARATUS FOR MAKINGYCONCENTRATED CARBON DIOXIDE Filed OGLlZ. 1921 gases ('Ondenoer ConyerZLArg-y 72m Cen? yy/WMM made from flue gases V50 be taken from the lastor Patented Mar. i, 1927.

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VIGGO DREWSEN, OF BROOKLYN, NEW YORK, ASSIGNOR TO WEST VIRGINIA. PULP AND PAPER COMPANY,

PROCESS AND OF NEW YORK, N. Y., A CORPORATION DELAWARE.

APPARATUS FOR MAKING CONCENTRATED CARBON DIXI'DE.

Application led October 12, 1921. Serial No. 507,875.

rlhis invention relates especially to processes and apparatus for chemically concentrating carbon dioxide so that if desired relatively strong or pure carbon dioxide can be orother weak gaseous mixtures. For this purpose the weak gases may be absorbed in suitable carbonate liquor such as a solution of sodium or potassium carbonate which may be eifected in one or more pressure absorption tanks. The carbon dioxide absorbed converts a corresponding amount of the sodium carbonate, for instance, into the relatively insoluble bi-carbonate which may be separated in a centrifugal separating device, the remaining carbonate li uor bein returned to (the absorptiori' tanks. e bi-car onate may be heated in a' steam jacketed or other heating pan to drive oif relatively pure carbon this may be eiectively done in strong sodium chloride or other suitable salt solution in which preferably the remaining carbonate is relatively insoluble so as to be separated by centrifugaldevices and returned to the absorption tanks, while the remaining salt solution may be continuously .or otherwise returned to the heating panor device, an illustrative apparatus for this purpose being shown-diagrammatically in the accompanying drawing.

In thel accompanyingudiagram a series of three or more tanks 1 w ch may have agitating devices of any suitable character, may be connected by the liquor ovu pipes 6 so that the carbonate liquor such as sodium carbonate solution or the like gradually passes from one to the other of these tanks through the pipes 6. At the same time, weak carbon dioxide ses such as kiln gases, containing 30 to 35% more or less of carbon dioxide, may be fed through the'pipes`2 under suitable pressure so as to be progressively absorbed in the tanks which are preferably operated under pressure, such as 60 to 100 pounds or so er square inch. The carbon dioxide is absor in these Itanks so as to more 'or less convert the or other carbonate into the bicarbonate which is, of course, insoluble, and the bicarbonate and suspending liquor may lowest tank 1 through the dischargeapipe 7 which may have the control valve or evice 12so'that regulated amounts are supplied to the centrifugal dioxide therefrom and separator device 8 which is preferably a continuous centrifugal shown diagrammatically. This operates to continuously separate the solid sodium bicarbonatewhich may be discharged from the centrifugal into the throat or hopper 13 while the carbonate liquor from the centrifugal is delivered through the pipe 9 which may lead to the pump or circulatingldevice 1 0 forcing the liquor back through t epipe 11 to one of the tanks 1.

In the converting tank or pan 15 the sodium bicarbonate may meet a substantially -saturated solution of sodium chloride at a temperature of about 110 C. which is maintained by the steam jacket 16 below. This boiling temperature of the solution drives oif concentrated carbon dioxide through the plpe or iiue- 17 while the material is being of the conveyor 14 by which itis carried to the converting tank 15 agitated and carried forward overor across the converting pan by conveyor 18. Finally, the solution drops down through the passage 19 into another continuous centrifugal 20, for instance, which separates therefrom the sodium carbonate which is substantially insoluble in the concentrated sodium chloride solution.

This crystallized sodium carbonateis thus discharged through the throat of passage 21 into the conveyor 22 of any suitable character which conveys it to the pipe or passage 5 communicating with the tanks 1. The

the screw or othercentrifugal 20 discharges the sodium chloride solution into pipe 23 from which it is returned through the pipe 24 into the converting pan 15 to again react with further' uantities of the sodium bicarbonate delivere to thepan.

If desired, of course, the passage or pipe 17 may communicate with a suitable coo r such as 25, of any suitable character, for coo A I ing or refrigerating the carbon dioxide and condensing and separating the steam therefrom, which flows back through the .passage d 17 into the converting pan while the carbon asses off through the pipe or pasdioxide sage 26 or recovery or treatment.

It will be obvious many changes in details may be made without departing from the spirit and scope of my invention.

' What I claim is:

urther liquefaction from the foregoing that carbon dioxide from 1. The process of making concentrated carbon dioxide from gases containing carbon, dioxide, which com rises forcing the said gases through a series of pressure absorption tanks and simultaneously passing sodium carbonate liquor throu h sai tanks in the opposite direction to e ect the proessive absorption of carbon dioxide by said iquor and its corresponding conversion into bicarbonate, centrifugally separating said bicarbonate from said liquor and returning the remaining carbonate liquor to said absorption tanks, mixing said bicarbonate with a saturated sodium chloride solution and heating the mixture to drive olf substantially concentrated carbon dioxide and simultaneously form relatively insoluble crystallized carbonate therein, centrifugally separating from said solution the crystallized carbonate and returning the saine to said absorption tanks, and returning the remainin salt solution for admixture with said bicar onate.

2. The process of making concentrated gases containing carbon dioxide, which comprises forcing the said gases through a series of absorption tanks and simultaneously passin sodium carbonate liquor through said tamis in the opposite direction to eiect the pro ive a sorption of carbon dioxide by sai liquor and its corresponding conversion into bicarbonate, centrifugally separating said bicarbonate from said liquor and returning the remaining carbonate li uor to said absorption tanks, mixing sai bicarbonate with a saturated sodium chloride solution and heating the mixture to drive ofi' substantially concentrated carbon dioxide and simultaneously form relatively insoluble crystallized carbonate therein and centrifugall se arating from said solution the crysta ize carbonate and returning the Same to said ab sorption tanks.

3. The process of making concentrated carbon dioxide `from gases containing carbon dioxide which comprises forcing the said gases through a series of pressure absorption and simultaneously passin carbonate liquor through said tanks in t e opposite direction to effect the progressive absorption of carbon dioxide by said liquor and its corres tri u lly separating said bicarbonate from said uor and returning the remaining carbonate li uor to said absorption tanks, mixin said icarbonate with a strong sodium ch oride salt solution and heating the mixture to drive oi substantially concentrated carbon dioxide and simultaneously form re1- atively insoluble crystallized carbonate therein, centrifugall separating from Said solution the crystal ized carbonate and returni'i the same to said absorption tanks.

4. e proce of making concentrated carbon dioxide from gases' containing carnding conversion into bicarbonate, cen-- bonate 1i uoi to said absorption tanks, mixing said icarbonate with a strong salt s0- lution and heating the mixture to drive oif substantially concentrated carbon dioxide.

5. The process of making concentrated carbon dioxide from weak gases containing carbon dioxide which comprises forcing the said gases through absorption tanks and simultaneously passing sodium carbonate liquor into said tankto effect the absorption of carbon dioxide by said liquor and its correspending conversion into bicarbonate, separating said bicarbonate from said li uor and returning the remaining carbonate quor to said absorption tank, mixing said bicarbonate with a strong salt solution and heating the mixture to drive off strong carbon dioxide and simultaneously formv relatively insoluble crystallized carbonate therein, and separating from said solution the crystallized carbonate and returning the same to said absorption tank.

6. The process of making concentrated carbon dioxide from weak gases containing carbon dioxide which comprises forcing the said gases through an absorption tank and passing sodium carbonate liquor into said tank to eiect the absorption of carbon dioxide by said liquor and its corresponding conversion into bicarbonate, separating said bicarbonate from said li uor mixing said bicarbonate with a salt so ution and heating the mixture to drive off strongl carbon dioxide and simultaneously form relatively insoluble crystallized carbonate therein, and separating from said solution the crystallized-carbonate.

7. The process of making iconcentrated carbon vdioxide from weak gases containingV carbon dioxide which comprises treating the said gases with sodium carbonate liquor to effect the absorption of carbon dioxide by series ofA pressure absoil'p- V .agitating means,

amasser bonate from said liquor and returning the remaining carbonate liquor to said absorption tanks and driving off substantially concentrated carbon dioxide from said bicarbonate.

9. The process of making concentrated carbon dioxide from gases containing carbon dioxide which com rises absorbing the said gases in sodium car onate liquor to effect its corresponding conversion into bicarbonate, centrifugally separating said sodium bicarbonate from said liquor and driving on and recovering substantially concentrated carbon dioxide fromsaid bicarbonate.

v10. The apparatus for producing concentrated carbon dioxide from gases containing carbon dioxide which comprises a connected series of pressure absorption tanks having a continuous centrifugal separator connected to said absorption tanks and cooperating means to return the remaining liquor to said tanks, a heated evaporating pan provided with a reflux condenser having a gas outlet and with a meand a conseparator.

chanicai discharge conveyor, nected continuous centrifugal 11. The apparatus for producing concentr-ated carbon dioxide from gases containing carbon dioxide which comprises a connected series of pressure absorption tanks, a centrifugal separator connected to said absorption tanks and cooperating means to return the remaining liquor to said evaporating pan denser having a gas outlet and chanicai discharge conveyor, nected centrifugal separator.

12. The apparatus for producing concentrated carbon dioxide from gases containing carbon dioxide which comprises a connected series vof absorption tanks having agitating means, a centrifugal separator connected to said absorption tanks and cooperating means vto return the remaining liquor to said tanks, and a heated evaporating pan provided with a reux condenser having a gas outlet.

t VIGGO DREWSEN;

with a meand a contanks, a heated provided with a reiux con- 

